General information. Nissan Almera (from 1995 to 1999 release)
Service of Nissan Almera from 1995 to 2000 in N15 body
1. General information
2. General requirements to car repairs
3. Operation and maintenance of the car
4. Petrol engines
5. Diesel engines
6. Transmission
7. Running gear
8. Steering
9. Brake system
9.1. General information
9.2. Brake mechanisms of forward wheels
9.3. Brake mechanisms of back wheels of drum type
9.4. Brake mechanisms of back wheels of disk type
9.5. Drive of brakes
9.6. Anti-blocking system of brakes
10. Electric equipment
11. Body
12. Appendices
13. Schemes of electric equipment
 









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9.1. General information

The working brake system with the hydraulic drive consists of two independent contours divided on diagonal (the left forward — right back, right forward — left back wheels). Forward brake mechanisms with the ventilated disks, back — drum.
Are the main brake cylinder with regulators of pressure of back brakes a part of the hydraulic drive of the working brake system, the vacuum amplifier and, depending on modification, anti-blocking system (ABS).
In the presence of ABS disk back brake mechanisms are used. Pressure regulators on cars with ABS are installed on a beam of a back suspension bracket.
On cars with the diesel engine the vacuum pump also is a part of the brake system.

Fig. 7.1. Brake mechanism of forward wheels of the CL22VD and CL22VE types:
1 — the directing fingers; 5 — a protective cover; 3 — a guide of brake shoes; 4 — a brake disk; 5 — clamping an insert of blocks; 6 — a brake shoe; 7 — clamping springs; 8 — shumogasyashchy laying;
9 — a bolt of fastening of a finger; 10 — the union for pumping; 11 — a support; 12 — a sealing ring; 13 — the piston; 14 — an antisplash cuff.


Brake mechanisms of forward wheels — with a floating bracket, one-piston, with the pig-iron ventilated disks (fig. 7.1).
Characteristics of the forward brake mechanism are specified in tab. 7.1.

Table 7.1   of the Characteristic of brake mechanisms of forward wheels
Characteristic
GA14DE engine
GA16DE, CD20 engines
Type
CL22VD
CL22VE
Diameter of the piston of the wheel cylinder, mm
54
Outer diameter of a brake disk, mm
232
247
Thickness of a disk, mm:
 
nominal
18
minimum admissible
16
Axial beating of a working surface of a disk, no more, than a mm
0,07
Unevenness of thickness of a disk, no more, than a mm
0,02
Length/width of brake shoes, mm
106/39,5
Thickness of frictional slips, mm:
 
nominal
11
minimum admissible
2
Brand of frictional slips
Akebono AP55HFF



Fig. 7.2. Drum brake mechanism of a back wheel of the LT18C type:
1 — a dustproof cuff; 2 — the piston; 3 — a cuff; 4 — the brake cylinder; 5 — the union for pumping; 6 — a spring; 7 — a cable of the parking brake;
8, 12, 13 — a basic rack of a block with a spring and a cup; 9 — a brake board;
10 — squeezing the lever; 11 — a squeezing brake shoe; 14 — the lower coupling spring of blocks; 15 — a spring of the mechanism of automatic adjustment of a gap; 16 — the brake drum; 17 — a clamping brake shoe; 18 — the mechanism of automatic adjustment of a gap; 19 — the top coupling spring of blocks


Brake mechanisms of back wheels drum, the LT18C type, with the mechanism of automatic adjustment of a gap and the built-in drive of the parking brake. Internal diameter of the brake cylinder is 15,87 mm, the internal diameter of a drum is 180 mm, 181 mm, maximum permissible after boring; ovality of a drum no more than 0,03 mm. Length of frictional slips is 172 mm, width is 30 mm. Thickness of frictional overlays of the Akebono A90TEE brand of 4 mm, minimum admissible — 1,5 mm. The device of the drum brake mechanism is shown in fig. 7.2.

Fig. 7.3. Disk brake mechanism of back wheels of the CL7HB type: 1 — the lever of the drive of the parking brake; 2 — a sealing ring;
3 — a lock ring; 4 — struts; 5 — a shaped washer; 6 — the bearing; 7 — a piston rod; 8 — the piston; 9 — a dustproof cuff; 10 — a sealing ring; 11 — a rod; 12 — a persistent washer of a spring; 13 — a spring; 14 — a clamping spring; 15 — clamping laying of blocks; 16 — bolts of fastening of the directing fingers; 17 — the directing fingers of brake shoes; 18 — protective covers of fingers; 19 — a guide of brake shoes; 20 — a brake disk; 21 — antinoise laying; 22 — a brake shoe


On cars with ABS disk back brake CL7HB mechanisms, one-piston, with a floating bracket (fig. 7.3) are installed. Diameter of the piston of the wheel cylinder of 30,23 mm. Outer diameter of a brake disk is 234 mm. Nominal thickness of a disk
7 mm, minimum admissible 6 mm. Length of brake shoes is 94 mm, width is 29 mm. Thickness of frictional slips is 10 mm, minimum admissible at wear of 1,5 mm. Brand of frictional slips Akebono AP52FF.
The main brake cylinder has two consistently working pistons and two built-in regulators of pressure of back brakes (option without ABS).
Internal diameter of the cylinder, mm:
without       ABS 20,64
with       ABS 22,22
Brake pressure of forward/back brakes, MPa:
without       ABS 6,5/3,5—3,9
with       ABS 7,5/5,2—5,6
Vacuum amplifier of the H195T brand of double action.
Diameter of a diaphragm of primary contour of 205 mm, secondary contour of 180 mm.
Distance from a body floor to a pedal (in a free state at application of effort of 490 — 500 N):
cars with the mechanical transmission — not less than 148 — 158 / 75 mm;
cars with the automatic transmission — not less than 157 — 167 / 85 mm.

Fig. 7.4. Details of system of the vacuum amplifier of models with the diesel engine: And — the CD20 engine; B — the CD20E engine (was issued since April, 1996): 1 — the generator; 2 — sealing rings; 3 — a rotor; 4 — blades; 5 — the case of the vacuum pump; 6 — a vacuum hose; 7 — the switch; 8 — clamps of hoses; 9 — a cover; 10 — the vacuum pump; 11 — a drain oil pipeline; 12 — the depression accumulator; 13 — the bringing oil pipeline


The vacuum pump on diesel CD20 engines is installed behind on a generator shaft. On diesel CD20E engines the vacuum pump is installed on a head of the block of cylinders and is given from the camshaft. Details of system of the vacuum amplifier are represented in fig. 7.4.
The system of the parking brake hummock hand-operated, affects brake mechanisms of back wheels. The drive lever at application of effort of 200 N has to move to 7 — 8 teeths of the ratchet mechanism.
The anti-blocking system of brakes of the Nippon Denso brand with an electronic control unit can be installed on all models of cars.
Are a part of ABS:
— the electronic control unit which is built in the hydrounit located in a forward part of a motor compartment at the left. The Electronic Control Unit (ECU) regulates by means of electromagnetic valves pressure in brake mechanisms, preventing blocking of wheels. Emergence of a tendency to blocking of one or several wheels is defined by sensors of speed of rotation of forward and back wheels. Also EBU obtains information on pressing a brake pedal from the stoplight switch;
— four induction sensors of speed of rotation of forward and back wheels;
— the relay of management and protection against power surges in onboard network;
— the control lamp of malfunction of system located in a combination of devices.

Fig. 7.18. Bolt of fastening of the sensor of speed of rotation of a forward wheel: 1 — the place for check of a gap of the sensor


Fig. 7.22. Check of a gap of the sensor of speed of rotation of a back wheel


— sensors of speed of rotation of forward and back wheels of inductive type, are installed on rotary fists of forward wheels and on an axis of a back nave opposite to gear rotors. Resistance of sensors is 800 — 1200 Ohms. The air gap (see fig. 7.18, 7.22) makes 0,1 — 1,1 mm and is not subject to adjustment;
— the hydrounit is located about the top fastening of the right forward rack of a suspension bracket. It consists of eight electromagnetic adjusting valves, the electric pump and the relay of inclusion of power supply installed on the relay block.

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9.2. Brake mechanisms of forward wheels